Factors associated with hazardous alcohol use in patients with psychiatric disorders: a cross-sectional study in the Neuro-Psycho-Pathological Centre of Kinshasa

Abstract

Background

Hazardous alcohol use frequently occurs among individuals with psychiatric disorders and may complicate clinical outcomes. However, there is limited evidence on its prevalence and associated factors in Sub-Saharan African psychiatric outpatient settings. This study aimed to estimate the prevalence of hazardous alcohol use and identify associated sociodemographic and clinical factors among patients receiving psychiatric care in Kinshasa, Democratic Republic of the Congo.

Methods

A cross-sectional analytical study was conducted at the Neuro-Psycho-Pathological Centre of Kinshasa over a period of 3 months (November 2023 to January 2024). Adults (≥ 18 years) with a documented psychiatric diagnosis attending outpatient follow-up were consecutively recruited. Data were collected via a structured questionnaire including the French version of the Alcohol Use Disorders Identification Test (AUDIT). Hazardous alcohol use was defined as an AUDIT score ≥ 10. Univariate logistic regression was used to screen variables; those with p-value < 0.20 entered a multivariate logistic regression model (forward stepwise). Multicollinearity was assessed (VIF < 2). Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) and p-values were reported.

Results

Of 204 participants, 190 (94.1%) reported regular alcohol consumption, and 121 (59.3%) met the threshold for hazardous alcohol use. In multivariate analysis, three variables were independently associated with hazardous alcohol use: increased alcohol consumption during the acute phase of psychiatric illness (aOR 5.21; 95% CI 2.40–11.34; p < 0.001), being in paid employment (aOR 2.28; 95% CI 1.01–5.14; p = 0.048), and having experienced a change or cessation of professional activity due to illness (aOR 2.15; 95% CI 1.02–4.52; p = 0.043).

Conclusions

More than half of psychiatric outpatients in Kinshasa exhibited hazardous alcohol use. Elevated consumption during symptomatic episodes, employment status, and occupational disruption were key correlates. These findings underscore the need for routine alcohol use screening and integrated psychosocial interventions in psychiatric services in low-resource settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12888-026-07873-w.

Background

Hazardous alcohol use (HAU) and psychiatric disorders often co-occur [1–3], posing significant clinical and public health challenges. Alcohol misuse is a significant contributor to global mortality and morbidity [4, 5], while psychiatric disorders are increasingly recognized as leading causes of disease burden worldwide [6]. The Global Burden of Disease (GBD) 2019 study reported that mental disorders remained among the top ten leading causes of burden worldwide, with no significant reduction in the global burden of mental disorders since 1990 [7], underscoring their persistent and widespread impact.

Individuals with psychiatric diseases are at increased risk of engaging in HAU, and conversely, individuals who engage in HAU frequently present with co-occurring psychiatric conditions. This bidirectional relationship is driven by a complex interplay of overlapping genetic, psychological, neurobiological, and social vulnerabilities. In clinical settings, these overlapping presentations often lead to underdiagnosis or undertreatment of either condition, especially when mental health systems are fragmented or under-resourced [8, 9].

Diagnosing comorbid psychiatric and HAU is challenging due to symptom overlap and the alcohol’s potential to exacerbate underlying mental health conditions. Some individuals use alcohol to self-medicate emotional distress or cope with social isolation or stigma [10], while others experience worsened psychiatric symptoms due to alcohol use. HAU is linked to more severe symptoms, functional impairment, higher hospitalization risk, and poor treatment adherence in individuals with mental health disorders [11]. This cycle complicates diagnosis and treatment, underscoring the need for integrated care addressing both psychiatric issues and alcohol-related risks. This need is particularly pressing in low-resource settings, such as the Democratic Republic of the Congo (DRC), where mental health care systems face profound challenges. These include limited financial resources, scarcity of culturally sensitive psychosocial interventions, the easy availability of alcohol and other psychoactive substances, and systemic barriers to treating comorbid conditions effectively [12].

Recent studies from other African countries and low- and middle-income countries (LMICs) have also highlighted the increasing prevalence of substance use among individuals with psychiatric disorders [13–15], further emphasizing the need for region-specific research to inform policy and intervention.

Despite these concerns, there is a paucity of data on the prevalence and factors associated with HAU among psychiatric patients in the DRC and across Sub-Saharan Africa. Addressing this knowledge gap is essential for designing locally appropriate, preventive mental health strategies.

Therefore, this study aimed to estimate the prevalence of HAU among patients receiving psychiatric care at the Neuro-Psycho-Pathological Centre of Kinshasa, and to identify factors associated with this behavior. By characterizing the extent and factors associated with HAU in this setting, we hope to inform more effective screening, prevention, and intervention strategies tailored to the needs of psychiatric patients in the DRC and similar low-resource environments.

Methods

Study design and participants

This cross-sectional study was conducted over a three-month period, from November 1, 2023 to January 31, 2024, at the Neuro-Psycho-Pathological Centre (CNPP) of the University of Kinshasa, Democratic Republic of the Congo.

Study population and sampling

Participants in this study included individuals aged 18 years and older who were attending psychiatric follow-up consultations at CNPP during the study period. Inclusion criteria included having a clinical diagnosis of psychiatric disorder, regardless of the specific nature of the disorder. Patients exhibiting acute psychiatric decompensation (e.g., psychosis, mania, or major depressive episode with psychotic features) and were unable to communicate effectively were excluded. A consecutive sampling approach was employed to recruit participants.

Data collection instruments and procedure

Data were collected using a structured and anonymous questionnaire administered by three trained mental health professionals. The questionnaire comprised five sections: (1) socio-demographic characteristics (2), clinical variables related to current psychiatric pathology (3), alcohol consumption patterns (4), use of other psychoactive substances, and (5) the Alcohol Use Disorder Identification Test (AUDIT). The first four sections were specifically developed for this study by mental health professionals in collaboration with the Statistics Department of the School of Public Health at the University of Kinshasa. The AUDIT is a validated screening tool developed by the World Health Organization (WHO) to assess alcohol consumption, drinking behaviors, and alcohol-related problems. In this study, the French version of the AUDIT [16] was used, consistent with previous studies involving high-risk clinical populations. While the WHO recommends a score of 8 as the general threshold for HAU, a higher threshold (AUDIT ≥ 10) was selected to improve specificity. Importantly, this threshold is not intended for diagnostic purposes, but rather to flag individuals at elevated risk for adverse outcomes. The AUDIT demonstrated excellent internal consistency in our sample, with a Cronbach’s alpha of 0.90. An English version of the complete data collection form is available as a supplementary file. The overall data collection process was closely supervised by the principal investigator, with regular quality control to ensure completeness and accuracy.

Operational definitions

• Regular Alcohol Consumption: Defined as the intake of alcoholic beverages at least once per week over the preceding 12 months, aligning with prior AUDIT-based research.

• Acute Phase: Refers to the period characterized by the presence of active psychiatric symptoms requiring intensive treatment.

• Stabilization Phase: Denotes the period during which psychiatric symptoms are controlled or in remission, and the patient is maintained on a stable treatment regimen.

Statistical analysis

Data were analyzed using IBM SPSS Statistics version 27.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics were used to characterize the study population. Categorical variables were presented as frequencies and percentages, while continuous variables were reported as means with standard deviations or medians with interquartile ranges, depending on distribution.

To explore factors associated with HAU, we first conducted a univariate analysis using chi-square tests (or Fisher’s exact tests when appropriate) and logistic regression. For each variable, odds ratios (ORs) with corresponding 95% confidence intervals (CIs) and p-values were calculated.

To ensure a comprehensive multivariable model while addressing concerns of overfitting, we included in the multivariate logistic regression model all variables with a p-value < 0.20 in the univariate analysis. This inclusive threshold was chosen to prevent premature exclusion of potentially relevant predictors. However, the variable “attempts to stop alcohol use” was deliberately excluded despite its statistical significance due to conceptual overlap with the outcome measure and risk of reverse causality.

The final model was built using forward stepwise selection to identify independent associations with hazardous alcohol use. Results were expressed as adjusted odds ratios (aORs) with 95% CIs and associated p-values. A p-value < 0.05 was considered statistically significant in the multivariate model.

To assess the robustness of the model, multicollinearity was evaluated using Variance Inflation Factors (VIFs), with all included variables showing VIF values < 2, indicating acceptable collinearity.

Results

Prevalence of HAU

Of the 204 psychiatric outpatients included in the study, 190 (94.1%) consumed alcohol on a regular basis. The average AUDIT score was 10.8 (SD = 3.5), on a scale ranging from 0 to 40. One hundred and twenty-one participants (59.3%) met the definition criteria for HAU, as shown in Table 1.

Table 1.

Average scores and frequency of HAU among participants

Variables	Frequency or mean (SD)	Percentage or min-max
AUDIT score	10.8 (3.5)	4.0–34.0
Regular alcohol consumption	190	94.1
HAU (n = 190)	121	59.3

SD, standard deviation; AUDIT, Alcohol Use Disorders Identification Test; HAU, hazardous alcohol use

Sociodemographic characteristics of the participants

As shown in Table 2, participants with HAU were significantly more likely to be gainfully employed compared to those without HAU. The same table indicates that there were no statistically significant differences between HAU and non-HAU participants regarding age, sex, marital status, education level, income source, or history of legal issues.

Table 2.

Sociodemographic characteristics of participants according to HAU status

Variable	Overall (n = 204)	No HAU (n = 83)	HAU (n = 121)	P
Age (years)	32.1 ± 10.5	33.0 ± 10.2	31.7 ± 10.3	0.405
Sex				0.450
Male	172 (84.3)	57 (68.7)	115 (95.4)
Female	32 (15.7)	12 (14.5)	20 (24.1)
Marital status				0.527
Unmarried	147 (72.1)	48 (57.8)	99 (81.8)
Married	36 (17.6)	11 (13.2)	25 (20.6)
Divorced	14 (6.9)	6 (7.2)	8 (6.6)
Widower	7 (3.4)	4 (4.8)	3 (2.5)
Educational level				0.396
primary and secondary	160 (78.4)	56 (64.5)	104 (86.0)
High School	44 (21.6)	13 (15.6)	31 (25.6)
Gainfully employed				< 0.01
Yes	157 (770)	46 (55.4)	111 (91.7)
No	47 (23.0)	23 (27.7)	24 (19.8)
Source of income				0.422
Oneself	137 (67.2)	45 (54.2)	92 (76.0)
Others	67 (32.8)	24 (29.0)	43 (35.5)
Presence of legal issues	65 (31.9)	25 (30.1)	40 (33.0)	0.686

Clinical characteristics of participants

Table 3 indicates that individuals with HAU, in comparison to those without HAU, more frequently reported a past experience of undergoing rehabilitation during periods between crises (69.1% vs. 56.6%, p = 0.001), as well as making shifts or completely stopping their occupation as a result of the condition (59.2% vs. 74.7%, p = 0.013). The other clinical characteristics, including insight, number of previous episodes, age at first episode, use of psychotropic therapy, and family history of mental disorders, were statistically comparable between individuals with HAU and those without HAU.

Table 3.

Clinical characteristics of participants according to HAU status

Variables	Overall (n = 204)	Non HAU (n = 83)	HAU (n = 121)	P
Insight				0.908
Good	200 (98.0)	82 (98.8)	118 (97.5)
Bad	4 (2.0)	1 (1.2)	3 (2.5)
Number of previous mental disorder episodes				0.615
Single episode	31 (15.2)	10 (12.0)	21 (17.3)
Two or more episodes	169 (82.4)	57 (68.7)	112 (92.6)
Age at first episode (years)	25.3 ± 8.50	24.3 ± 7.01	26.0 ± 9.22	0.206
Being on psychotropic treatment				0.882
Yes	181 (88.7)	62 (74.7)	119 (63.3)
No	23 (11.3)	7 (8.4)	16 (65.0)
Presence of family history of mental disorder				0.663
Yes	118 (57.8)	38 (45.8)	80 (64.8)
No	86 (4.2)	31 (37.3)	55 (61.7)
Similarity between the nature of psychiatric disorders in the family and that of the patient				0.478
Yes	113 (55.4)	36 (43.4)	77 (65.7)
No	91 (44.6)	33 (39.7)	58 (60.7)
Rehabilitation during periods between crises				0.001
Yes	161 (78.9)	47 (56.6)	114 (69.1)
No	43 (21.1)	22 (26.5)	21 (40.5)
Change or cessation of the occupation following the disorder				0.013
Yes	164 (80.4)	62 (74.7)	102 (59.2)
No	40 (19.6)	7 (8.4)	33 (81.1)

Alcohol use history and patterns

As outlined in Table 4, compared to participants without HAU, those with HAU were more often aware that alcohol consumption could cause health problems (90.9% vs. 60.2%, p = 0.005), had more likely to have made at least one attempt to stop drinking (100% vs. 67.5%, p < 0.001) and were more likely to report increased consumption during the acute phase of the disease (86.8% vs. 39.7%, p < 0.001). The remaining characteristics (the age at which alcohol use began, whether it was used alone or in a group, whether it preceded or not the psychiatric symptoms, whether multiple drugs were used, and whether there were any legal issues associated with this consumption) showed no significant differences between participants with and without AUD.

Table 4.

Characteristics of participants’ alcohol intake patterns based on their HAU status

Variables	Overall (n = 204)	No HAU (n = 83)	HAU (n = 121)	P
Age at beginning of alcohol consumption (years)	20.8 ± 4.77	20.7 ± 3.99	20.9 ± 5.17	0.821
Mode of consumption				0.081
Alone	118 (57.8)	36 (43.4)	82 (67.6)
In a group	73 (35.8)	32 (38.5)	41 (33.9)
Alcohol use prior to onset of psychiatric disorder				0.565
Yes	159 (78.0)	55 (66.2)	104 (95.9)
No	32 (15.7)	13 (15.6)	19 (15.7)
Drinking alcohol is perceived as a potential cause of health problems.				0.005
Yes	160 (78.4)	50 (60.2)	110 (90.9)
No	31 (15.2)	18 (21.7)	13 (10.7)
Multiple drugs use				0.637
Yes	99 (48.5)	37 (44.6)	62 (51.2)
No	92 (45.1)	31(37.3)	61 (50.4)
Problems with police following alcohol consumption				0.892
Yes	98 (48.0)	35 (42.2)	63 (52.1)
No	93 (45.6)	33 (39.3)	60 (49.6)
Attempts to stop alcohol consumption				< 0.001
Yes	177 (86.7)	56 (67.5)	121 (100)
No	14 (6.8)	12 (14.5)	2 (1.6)
Phase of illness where alcohol consumption is highest Acute-phase Stabilization phase	138 (67.6) 53 (25.96)	33 (39.7) 35 (42.2)	105 (86.8) 18 (14.9)	< 0.001

Factors associated with hazardous alcohol use

As shown in Table 5, several variables showed a significant or near-significant association with HAU in the univariate analysis. These include paid employment (OR: 2.42; 95% CI: 1.15–5.12; p = 0.020), intercritical rehabilitation (OR: 1.94; 95% CI: 0.92–4.10; p = 0.081), career change or cessation following illness (OR: 1.85; 95% CI: 0.91–3.79; p = 0.092), cumulative alcohol consumption during the acute phase of the illness (OR: 6.43; 95% CI: 3.19–12.93; p < 0.001), perception of alcohol as harmful (OR: 2.27; 95% CI: 1.10–4.68; p = 0.027), and male sex (OR: 1.81; 95% CI: 0.82-4.00; p = 0.140), duration of illness ≥ 5 years (OR: 1.64; 95% CI: 0.86–3.14; p = 0.133), living alone (OR: 1.78; 95% CI: 0.92–3.43; p = 0.090) and family history of alcoholism (OR: 2.10; 95% CI: 1.00–4.39; p = 0.050).

Table 5.

Univariate and multivariate logistic regression analyses of factors associated with HAU

Variables	Univariate analysis		Multivariate analysis
	p	OR (IC95%)	P	aOR (IC95%)
Gainful employment
No  Yes	0.020	1 2.42 (1.15–5.12)	0.048	1 2.28 (1.01–5.14)
Intercrisis rehabilitation
No  Yes	0.081	1 1.94 (0.92–4.10)	0.474	1 1.39 (0.56–3.41)
Having changed profession following illness
No  Yes	0.092	1 1.85 (0.91–3.79)	0.043	1 2.15 (1.02–4.52)
Stage of the disease with high alcohol consumption:
Stabilization phase  Acute phase	< 0.001	1 6.43 (3.19–12.93)	< 0.001)	1 5.21 (2.40–11.34
Alcohol perceived as a source of health problems
No  Yes	0.027	1 2.27 (1.10–4.68)	0.512	1 1.34 (0.56–3.17)
Male sex
No  Yes	0.140	1 1.81 (0.82–4.00)	0.345	1 1.53 (0.63–3.72)
Duration of illness ≥ 5 years
No  Yes	0.133	1 1.64 (0.86–3.14)	0.539	1 1.29 (0.57–2.93)
Live alone
No  Yes	0.090	1 1.78 (0.92–3.43)	0.390	1 1.45 (0.62–3.38)
Family history of alcoholism
No  Yes	0.050	1 2.10 (1.00–4.39)	0.255	1 1.61 (0.71–3.66)

After adjustment, three factors remained significantly associated with HAU:

• Increased consumption during the acute phase of the psychiatric illness (aOR: 5.21; 95% CI: 2.40–11.34; p < 0.001),

• Paid employment (aOR: 2.28; 95% CI: 1.01–5.14; p = 0.048),

• Changing or ceasing employment (aOR: 2.15; 95% CI: 1.02–4.52; p = 0.043).

None of the other included variables showed a significant association in the adjusted model. No multicollinearity was detected (all FIVs < 2). The multivariate logistic regression model demonstrated acceptable calibration (Hosmer–Lemeshow p = 0.41) and moderate explanatory power (Nagelkerke R² = 0.31).

Discussion

The study revealed a high prevalence of regular alcohol consumption (94.1%). The very high prevalence of regular alcohol use in our sample (94.1%) may reflect multiple contextual factors, including cultural norms of widespread alcohol availability, low levels of stigma around drinking, and economic stressors that promote substance use as a coping mechanism. Additionally, selection bias may have occurred, as our sample consisted of psychiatric patients able to communicate during follow-up consultations, potentially excluding more severely ill or abstinent individuals.

The prevalence of HAU was 59.3% among individuals receiving psychiatric care at the Neuro-Psycho-Pathological Centre of Kinshasa, a figure significantly higher than those reported in several other international contexts. Lower frequencies were found in high-income countries like Sweden (22% of women and 30% of men) [17] and Australia (17%) [18]. A slightly higher prevalence (49%) but still lower than the present study was found in the UK among patients admitted to acute general psychiatry services [19]. In contrast, much lower rates were observed in Asian populations, notably 10.5% in Taiwan among patients with schizophrenia or mood disorders [20] and 5.5% in a rural Indian cohort [21] with schizophrenia. In sub-Saharan Africa, a study conducted in north-western Ethiopia reported a prevalence of 23.5% among patients with severe mental disorders. These comparisons suggest that HAU may be particularly prevalent among psychiatric patients in low-resource urban settings like Kinshasa, likely due to sociocultural norms, exposure to stress, poor integration of services, and easy access to alcohol.

This comorbidity can lead to various severe consequences, affecting both the course and treatment outcomes of mental disorders [1]. In addition, this comorbidity can increase the incidence of various diseases, including hypertension [22], cardiovascular disease [23], HIV/AIDS infection [24], cirrhosis [25] and accidental injuries [26], as well as behavioral disorders such as suicidality [27], violence/aggressiveness [28] and social relationship problems [29]. Moreover, it can result in nonadherence to treatments [30], relapse of psychiatric disorders, an increase in the cost of health care, and a reduction in quality of life among patients with severe mental disorders [31]. Furthermore, the coexistence of HAU and psychiatric disorders might mutually intensify, leading to poorer outcomes [32]. Therefore, individuals who have HAU and psychiatric problems are more likely to relapse to alcohol use more often and have more severe psychiatric symptoms [33]. In this study, we defined HAU by a total AUDIT score greater than or equal to 10. The AUDIT, developed by the WHO, is a widely used screening tool designed to detect individuals at risk of alcohol-related harm. According to WHO guidelines, AUDIT scores are categorized as follows: 0–7 as low risk, 8–15 as hazardous use, 16–19 as harmful use and ≥ 20 as probable dependence. While the lower bound of 8 is commonly used to screen for hazardous drinking, different thresholds, such as 11 in the study by Verhoog et al. [34] may be applied for various reasons. We selected a cut-off of ≥ 10 to prioritize specificity over sensitivity in our psychiatric sample, deeming it appropriate for identifying probable HAU. Given that the AUDIT serves as a screening rather than a diagnostic tool, interpretation of prevalence and associated factors should be contextualized accordingly. Future studies could consider applying multiple cut-offs to facilitate comparison of results.

Our findings are consistent with earlier research showing a greater frequency of HAU among individuals with mental disorders than among the general population [35, 36]. Different studies in developing countries also reported a high rate of HAU comorbidity in patients with psychiatric disorders, with frequencies ranging from 11.3% to 56% in patients with affective disorders [36, 37] and 9.7% to 74% in patients with schizophrenia [36, 38]. There is a lack of HAU incidence studies among psychiatric patients in sub-Saharan African countries. One of the few existing studies conducted in Northwest Ethiopia reported a prevalence of 23.5% of HAU among patients with severe mental disorders [38], which is less than half of that found in this study.

The wide range of prevalence rates in these studies can be due to variations in study contexts, study design, types of psychiatric disorders seen in the populations being studied, and the screening method used for the diagnosis of HAU.

In the present study, participants with HAU were more likely to be gainfully employed than were those without HAU. This finding is in accordance with that of Namrata Walia et al., who reported that being employed was more strongly associated with alcohol consumption [39].

The current study revealed that persons with HAU reported a greater incidence of previous participation in recovery programs during periods of remission, as well as experiencing changes or cessation of their employment due to the disease. This finding highlights both the impact of HAU on the course of the disease and its potential impact on professional careers, in line with the work of Michael French et al. [40].

This study also revealed that individuals with HAU were more aware of the potential health risks associated with alcohol use, made more frequent attempts to quit drinking, and were significantly more prone to alcohol use during the acute phase of the condition. This inability for the individual to stop drinking despite motivation and recognition of the harmful effects of alcohol constitutes the very definition of alcohol addiction. Significant progress has been made in recent years in understanding the underlying pathophysiological mechanisms of this addiction, ranging from changes within cells to changes in neural circuits [41]. This finding offers hope for identifying new therapeutic targets and developing much-needed effective treatment options. The propensity to drink more alcohol during periods of psychiatric pathology relapse reflects the influence of psychiatric pathology on HAU. It is challenging to determine whether the mental pathology worsened the HAU or whether the HAU triggered the relapse of the psychiatric disease.

The multivariate analysis revealed three factors that remained significantly associated with HAU among psychiatric outpatients: (1) increased alcohol consumption during the acute phase of the illness (2), being gainfully employed, and (3) having experienced a change or cessation of professional activity due to the psychiatric condition.

The strongest association was observed for increased alcohol consumption during acute psychiatric episodes, with a five-fold increase in the likelihood of HAU (aOR: 5.21; 95% CI: 2.40–11.34). Increased alcohol use during acute psychiatric phases may reflect maladaptive self-medication behavior, where individuals attempt to alleviate psychological distress in the absence of adequate support. In Ethiopian populations, alcohol use disorders have been shown to correlate positively with common mental distress and co-occurring psychiatric symptoms, suggesting that drinking may serve as a coping mechanism in the context of insufficient mental health resources. Studies of psychiatric and community samples in Ethiopia have likewise reported high co-occurrence of hazardous alcohol use and mental health symptoms, consistent with self-medication hypotheses [42, 43]. During periods of heightened distress, agitation, or psychotic symptoms, patients may use alcohol as a coping mechanism or means of temporary relief, which unfortunately contributes to worsening clinical trajectories. This finding underscores the importance of systematic screening and targeted intervention during destabilization phases of psychiatric illness, when patients may be particularly vulnerable to escalating alcohol misuse.

Interestingly, gainful employment was also found to be independently associated with hazardous alcohol use (aOR: 2.28; 95% CI: 1.01–5.14). While employment is often assumed to be protective, evidence from sub–Saharan Africa suggests that economically active individuals and certain work groups may have higher rates of alcohol use due to increased social exposure, occupational norms, and alcohol accessibility. For example, occupation was significantly associated with alcohol use in a large Ugandan cohort, with higher odds of drinking observed in fishermen and bar/restaurant workers compared to agricultural laborers [44]. Systematic evidence from the region further highlights socio economic gradients in alcohol consumption patterns, reflecting broader structural influences on drinking behaviors [45, 46]. This tendency of gainfully employed individuals being more likely to engage in HAU was previously described by Subramaniam et al. [36]. While employment is often considered a protective factor in mental health, this result suggests a more nuanced relationship in this context. Employed individuals may be exposed to increased occupational stress, peer pressure, or socioeconomic environments that normalize or facilitate alcohol consumption. In low-resource settings such as Kinshasa, work-related strain and lack of access to structured psychosocial support may compound vulnerability to hazardous drinking, especially in individuals with underlying psychiatric disorders.

The third significant factor, which is the change or cessation of professional activity due to psychiatric illness (aOR: 2.15; 95% CI: 1.02–4.52), may reflect the bidirectional burden of illness and alcohol use. Disruption of one’s professional life often leads to reduced self-esteem, social isolation, and economic hardship, all of which may increase the risk of maladaptive coping behaviors such as alcohol use. Conversely, problematic alcohol consumption may itself contribute to occupational impairment, making it difficult to determine directionality in a cross-sectional study. Nonetheless, this finding highlights the need for psychosocial rehabilitation and vocational support as part of integrated care for dual-diagnosis patients.

Although other variables such as sex, family history of alcohol use, and duration of illness showed moderate associations in univariate analysis, they were not retained in the final model. However, previous studies conducted in Africa have found an independent association between these factors and HAU [43, 47]. Their effects may be mediated through other pathways or confounded by stronger behavioral or social predictors.

Overall, these results suggest that HAU among psychiatric patients is not merely driven by clinical severity or biological vulnerability, but also by social determinants such as employment dynamics and the psychosocial consequences of psychiatric illness. The findings reinforce the need for integrated screening and tailored interventions, particularly during acute psychiatric episodes and life transitions that threaten occupational stability.

While our findings mirror those from studies in other low- and middle-income countries, the reported prevalence of HAU in psychiatric populations varies widely depending on the diagnostic focus, cultural context, and screening approach used. The results of this study provide context-specific evidence that supports the need for integrated substance use services in psychiatric care facilities across sub-Saharan Africa.

However, several limitations must be acknowledged. First, the use of AUDIT ≥ 10 as a threshold for hazardous alcohol use is not a universally validated standard for psychiatric populations. The use of this relatively low AUDIT threshold may also have contributed to the high prevalence of hazardous alcohol use observed in this study. Different cut-off points (e.g., ≥ 13 for men, ≥ 12 for women, or ≥ 20 for probable dependence) could yield different prevalence estimates or associations. Second, the cross-sectional design precludes any conclusions regarding causality or directionality of associations. Third, reliance on self-report introduces potential for recall bias or social desirability effects, especially among individuals with fluctuating insight or cognitive impairment. Fourth, due to the heterogeneity of psychiatric diagnoses in our sample and the absence of standardized diagnostic validation, we were unable to explore disorder-specific relationships with alcohol use. Fifth, although multicollinearity was assessed and ruled out statistically (variance inflation factors < 2), conceptual overlap among behavioral variables remains a methodological consideration. Lastly, the study did not perform sensitivity analyses using alternative AUDIT thresholds (e.g., ≥ 8 or ≥ 13/20). Future research with larger samples is warranted to examine the robustness of associations across different definitions of hazardous or dependent drinking.

Conclusion

This study documents a substantial burden of HAU among individuals receiving psychiatric care in Kinshasa. Increased alcohol consumption during acute psychiatric episodes, paid employment, and occupational disruption due to illness was found to be key associated factors associated with HAU.

These findings underscore the need for routine screening for hau in psychiatric settings, especially during periods of symptom exacerbation and among individuals facing professional or social stressors. In resource-limited health systems such as those in Sub-Saharan Africa, integrating brief alcohol interventions and psychosocial support into mental health services is both necessary and urgent.

Future research directions

Given the cross-sectional design of the present study, future research should adopt longitudinal methodologies to better understand the temporal relationship between HAU and psychiatric symptom dynamics. Prospective studies would help determine whether increased alcohol consumption acts as a precipitant of psychiatric exacerbation, a consequence of symptom burden, or both.

Additionally, future investigations should aim to incorporate standardized psychiatric diagnostic tools (e.g., MINI, SCID) to allow for diagnostic specificity. This would enable the assessment of whether particular psychiatric disorders, such as schizophrenia, bipolar disorder, or major depression, confer differential risks for HAU and how comorbid substance use evolves across diagnostic categories.

Further studies should also explore the impact of protective psychosocial factors, such as family support, therapeutic alliance, and resilience, and assess how occupational functioning and work-related stress contribute to hazardous drinking among patients with mental illness.

Finally, implementation research is needed to evaluate the feasibility, acceptability, and effectiveness of integrated dual-diagnosis interventions within psychiatric care frameworks in low-resource settings. Locally adapted screening tools, brief intervention protocols, and culturally relevant psychoeducation models should be tested to inform scalable mental health and substance use service delivery in Sub-Saharan Africa.

Supplementary Information

Below is the link to the electronic supplementary material.

Abbreviations

aOR

adjusted odds ratio

HAU

Hazardous Alcohol Use

AUDIT

Alcohol Use Disorders Identification Test

CI

Confidence interval

CNPP

Centre Neuro Psychopathologique

DSM-5

Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition

OR

Odds ratio

SD

Standard deviation

WHO

World Health Organization

Author contributions

Design and concept of the study: DBB, PNB, and BKP. Acquisition of data: PNB, and DBB. Manuscript draft: DBB, PNB and BKP. Analysis and interpretation of the data: ANN, PNB, MB, PTM, JTN, JBK, DBB, and BKP. All authors have read and approved the final manuscript.

Funding

None.

Data availability

Because the consent given by the study participants did not include data sharing with third parties, anonymized data can be made available to investigators for analysis upon reasonable request to the corresponding author.

Declarations

Ethics approval and consent to participate

The ethics committee of the School of Public Health of the University of Kinshasa (reference number: ESP/CE/167/2023) reviewed and approved this study, and all the included patients provided written informed consent. The rules of confidentiality and ethics were respected according to the 1964 Declaration of Helsinki.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.